Climate Change May Cause Pacific Coral Reef Fish to Drop by 20 Percent

There will be winners and losers when it comes to climate change. Some areas will flourish while others will feel the full, negative impacts. Unfortunately for Pacific islands, they may be some of the losers as temperatures shift and weather conditions change. Scientists have discovered that coral reef fish, which are an essential source of food for islanders, could drop by as much as 20 percent by 2050.

In order to examine how fish populations might be affected by the changing climate, researchers studied forecasts from the Intergovernmental Panel on Climate Change (IPCC). More specifically, they examined the response of skipjack, a fish in the tuna family that makes up 90 percent of catches. With its long, silvery body and bright red meat, these fast-swimming fish are common in tropical waters throughout the world. According to the models, there will be a rise in surface water temperature that will be greater in the western ocean.

So what effect will this have on fish populations? The warmer temperatures will cause tuna to migrate toward eastern Polynesia. Because of this, catchment areas will move away from the Melanesian coast, the Salomon islands or Papua New Guinea. In addition, the availability of coral fishes along the coasts will also decrease as habitat declines. Coral reef recovery is expected to fall from 40 percent to 10 to 20 percent by 2050. This means that the number of coral fish available will be reduced by 20 percent.

Needless to say, this is bad news for island nations. Tuna in particular is a huge economic resource. As populations move to cooler waters, fishing rights paid by major international fisheries may no longer be given to small, insular nations.

That's not to say that the situation is hopeless, though. Pacific island nations could potential turn to aquaculture and fresh-water fisheries. Rainfall is expected to rise significantly, which means that the surfaces of lakes and rivers will increase by as much as 10 percent. This could potentially help make up for expected losses.

The findings are published in the journal Nature Climate Change.